"I am particularly pleased to be following in the footsteps of Tom Kilgore, an outstanding leader whom I have long admired," Johnson says. "TVA and the people who work there have had a dramatic positive impact on the quality of life in the Tennessee Valley, and I look forward to being a part of the dynamic team serving the people of the region."

Johnson most recently served as CEO of Progress Energy, where he was instrumental in brokering the merger between Progress and Duke Energy in 2011.

It was expected that Johnson would supplant Duke CEO Jim Rogers as head of the newly-formed company, but Duke -- whose shareholders reportedly own 63% of the combined company -- announced Rogers would maintain his position shortly before the merger was completed.

The Tennessee Valley Authority says Kilgore will continue leading the US$11 billion federal agency until Johnson's arrival, then help in the transition period following.

TVA is a federally funded utility established in 1933 by Congress to develop systems of delivery for electricity and management of natural resources. Today, TVA maintains 29 hydroelectric projects, along with a pumped-storage facility and several externally owned dams.